QtWidgets: replace 0 with \nullptr in documentation

Replace 0 with \nullptr in the documentation.
As a drive-by also replace some 0 with nullptr in the corresponding
code.

Change-Id: Id8056dc2364a372e40bc04e8cb9fcc443e49fb18
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

4 files changed, 16 insertions, 15 deletions

diff --git a/src/widgets/itemviews/qabstractitemview.cpp b/src/widgets/itemviews/qabstractitemview.cpp
index 1151379e17..7441161e13 100644
--- a/src/widgets/itemviews/qabstractitemview.cpp
+++ b/src/widgets/itemviews/qabstractitemview.cpp
@@ -940,8 +940,8 @@ void QAbstractItemView::setItemDelegateForRow(int row, QAbstractItemDelegate *de
    \since 4.2
 
    Returns the item delegate used by this view and model for the given \a row,
-   or 0 if no delegate has been assigned. You can call itemDelegate() to get a
-   pointer to the current delegate for a given index.
+   or \nullptr if no delegate has been assigned. You can call itemDelegate()
+   to get a pointer to the current delegate for a given index.
 
    \sa setItemDelegateForRow(), itemDelegateForColumn(), setItemDelegate()
 */
diff --git a/src/widgets/itemviews/qcolumnview.cpp b/src/widgets/itemviews/qcolumnview.cpp
index 1fe17721ba..a4eed2d885 100644
--- a/src/widgets/itemviews/qcolumnview.cpp
+++ b/src/widgets/itemviews/qcolumnview.cpp
@@ -801,7 +801,7 @@ void QColumnView::initializeColumn(QAbstractItemView *column) const
 }
 
 /*!
-    Returns the preview widget, or 0 if there is none.
+    Returns the preview widget, or \nullptr if there is none.
 
     \sa setPreviewWidget(), updatePreviewWidget()
 */
diff --git a/src/widgets/itemviews/qtableview.cpp b/src/widgets/itemviews/qtableview.cpp
index a7d144672c..dd43c6d3e4 100644
--- a/src/widgets/itemviews/qtableview.cpp
+++ b/src/widgets/itemviews/qtableview.cpp
@@ -138,20 +138,21 @@ void QSpanCollection::updateSpan(QSpanCollection::Span *span, int old_height)
 }
 
 /** \internal
- * \return a spans that spans over cell x,y  (column,row)  or 0 if there is none.
+ * \return a spans that spans over cell x,y  (column,row)
+ * or \nullptr if there is none.
  */
 QSpanCollection::Span *QSpanCollection::spanAt(int x, int y) const
 {
     Index::const_iterator it_y = index.lowerBound(-y);
     if (it_y == index.end())
-        return 0;
+        return nullptr;
     SubIndex::const_iterator it_x = (*it_y).lowerBound(-x);
     if (it_x == (*it_y).end())
-        return 0;
+        return nullptr;
     Span *span = *it_x;
     if (span->right() >= x && span->bottom() >= y)
         return span;
-    return 0;
+    return nullptr;
 }
 
 
diff --git a/src/widgets/itemviews/qtreewidget.cpp b/src/widgets/itemviews/qtreewidget.cpp
index 6050bcd616..29cc199526 100644
--- a/src/widgets/itemviews/qtreewidget.cpp
+++ b/src/widgets/itemviews/qtreewidget.cpp
@@ -2539,8 +2539,8 @@ void QTreeWidgetPrivate::_q_dataChanged(const QModelIndex &topLeft,
     QStyle::SH_ItemView_ActivateItemOnSingleClick style hint) or
     pressing a special key (e.g., \uicontrol Enter).
 
-    The specified \a item is the item that was clicked, or 0 if no
-    item was clicked. The \a column is the item's column that was
+    The specified \a item is the item that was clicked, or \nullptr if
+    no item was clicked. The \a column is the item's column that was
     clicked, or -1 if no item was clicked.
 */
 
@@ -2550,8 +2550,8 @@ void QTreeWidgetPrivate::_q_dataChanged(const QModelIndex &topLeft,
     This signal is emitted when the user presses a mouse button inside
     the widget.
 
-    The specified \a item is the item that was clicked, or 0 if no
-    item was clicked. The \a column is the item's column that was
+    The specified \a item is the item that was clicked, or \nullptr if
+    no item was clicked. The \a column is the item's column that was
     clicked, or -1 if no item was clicked.
 */
 
@@ -2571,8 +2571,8 @@ void QTreeWidgetPrivate::_q_dataChanged(const QModelIndex &topLeft,
     This signal is emitted when the user double clicks inside the
     widget.
 
-    The specified \a item is the item that was clicked, or 0 if no
-    item was clicked. The \a column is the item's column that was
+    The specified \a item is the item that was clicked, or \nullptr if
+    no item was clicked. The \a column is the item's column that was
     clicked. If no item was double clicked, no signal will be emitted.
 */
 
@@ -2724,8 +2724,8 @@ QTreeWidgetItem *QTreeWidget::invisibleRootItem() const
 }
 
 /*!
-  Returns the top level item at the given \a index, or 0 if the item does
-  not exist.
+  Returns the top level item at the given \a index, or \nullptr if the
+  item does not exist.
 
   \sa topLevelItemCount(), insertTopLevelItem()
 */